front 1 A child has severe recurrent viral and fungal infections because thymic development failed. Which diagnosis best fits? A. Wiskott-Aldrich syndrome B. Hyper-IgM syndrome C. DiGeorge syndrome D. Canale-Smith syndrome | back 1 C. DiGeorge syndrome |
front 2 In DiGeorge syndrome, absent thymic tissue most directly impairs development of which organ? A. Thymus B. Spleen C. Bone marrow D. Lymph node | back 2 A. Thymus |
front 3 A patient with DiGeorge syndrome has profound cellular immune dysfunction. Which cell type is primarily affected? A. B cells B. Neutrophils C. Macrophages D. T cells | back 3 D. T cells |
front 4 The life-threatening infections in DiGeorge syndrome are mainly due to loss of which immune function? A. Antibody secretion B. T-cell function C. Complement activation D. Neutrophil migration | back 4 B. T-cell function |
front 5 Which sequence correctly lists the major phases of HIV infection? A. Acute, latent, recovered B. Acute, chronic, profound immunosuppression C. Chronic, acute, latent D. Prodrome, remission, recovery | back 5 B. Acute, chronic, profound immunosuppression |
front 6 After HIV enters a target cell, which enzyme copies viral RNA into DNA? A. DNA polymerase B. RNA primase C. Reverse transcriptase D. RAG recombinase | back 6 C. Reverse transcriptase |
front 7 Reverse transcriptase converts HIV genetic material into which product? A. cDNA B. mRNA C. rRNA D. tRNA | back 7 A. cDNA |
front 8 After reverse transcription, which event allows HIV DNA to persist inside the host genome? A. Capsid degradation B. Ribosomal binding C. Antibody neutralization D. Insertion into host DNA | back 8 D. Insertion into host DNA |
front 9 Once HIV DNA is inserted into host DNA and remains inactive, which effector cells fail to detect it? A. B cells B. NK cells C. CTLs D. Neutrophils | back 9 C. CTLs |
front 10 A patient is born with nonfunctional CD40L. Which co-stimulatory pathway is directly defective? A. CD28-B7 B. CD40-CD40L C. Fas-FasL D. IgE-Fc receptor | back 10 B. CD40-CD40L |
front 11 Loss of functional CD40 or CD40L most directly prevents which immune response? A. T-dependent antibody response B. NK-cell cytotoxicity C. Neutrophil oxidative burst D. Complement membrane attack | back 11 A. T-dependent antibody response |
front 12 A patient with defective CD40 signaling has impaired germinal-center function. Which two processes are compromised? | back 12 Class switching and hypermutation |
front 13 Without functional CD40/CD40L signaling, antibody production is biased toward which class? | back 13 IgM |
front 14 Which immunodeficiency syndrome eliminates both major adaptive lymphocyte arms? | back 14 SCID |
front 15 Severe combined immunodeficiency involves dysfunction of which lymphocyte groups? | back 15 B and T cells |
front 16 A patient with a congenital C3 defect has lymph nodes lacking which structure? ____ ____ | back 16 Germinal centers |
front 17 A C3-deficient patient lacks germinal centers. Which antibody class would B cells mainly produce? | back 17 A. IgM |
front 18 Initial HIV transmission commonly begins after viral penetration through which barrier? A. Respiratory epithelium B. Keratinized skin C. Gastric mucosa D. Rectal or vaginal mucosa | back 18 D. Rectal or vaginal mucosa |
front 19 After crossing mucosal surfaces, HIV initially infects which target cell population? A. B cells B. Neutrophils C. T cells D. Eosinophils | back 19 C. T cells |
front 20 Once inside T cells, HIV replicates by taking over which resource? A. Complement proteins B. Host machinery C. Granule enzymes D. Antibody genes | back 20 B. Host machinery |
front 21 During acute HIV infection, viral replication across the body does what? A. Stops immediately B. Remains localized C. Clears completely D. Multiplies systemically | back 21 D. Multiplies systemically |
front 22 During acute HIV infection, viral levels typically peak at approximately what time? A. 3-4 weeks B. 2-3 days C. 6-8 months D. 1-2 years | back 22 A. 3-4 weeks |
front 23 During the chronic phase of HIV infection, what happens to viral levels? A. Disappear completely B. Peak immediately C. Decline but persist D. Remain undetectable | back 23 C. Decline but persist |
front 24 As HIV progresses toward profound immunosuppression, what ultimately explains susceptibility to fatal infections? Loss of ____ cells | back 24 Loss of T cells |
front 25 HIV-1 stores its genetic information in which nucleic acid form? | back 25 RNA |
front 26 Why can killer T cells fail to detect HIV-infected cells during latency? A. HIV destroys antibodies B. HIV blocks all cytokines C. HIV exits immediately D. HIV remains hidden intracellularly | back 26 D. HIV remains hidden intracellularly |
front 27 A newly infected patient asks whether HIV is detected immediately. Which feature explains delayed immune recognition? A. Acute sterilization B. Latent cellular buildup C. Permanent antibody absence D. Immediate viral clearance | back 27 B. Latent cellular buildup |
front 28 During the latent period of HIV, infected cells mainly serve as what? A. Complement reservoirs B. Reactivatable viral reservoir C. Neutrophil traps D. IgE-producing cells | back 28 B. Reactivatable viral reservoir |
front 29 Each HIV replication cycle introduces mutations. What is the immune consequence? A. Easier T-cell recognition B. Faster complement fixation C. Reduced viral diversity D. Harder immune recognition | back 29 D. Harder immune recognition |
front 30 High mutation rates help HIV maintain which advantage? A. Immune escape B. Antibody deletion C. Eosinophil recruitment D. Mast-cell activation | back 30 A. Immune escape |
front 31 Which set contains the major HIV-1 target cells? A. B cells, eosinophils, neutrophils B. NK cells, basophils, mast cells C. Helper T cells, macrophages, dendritic cells D. Platelets, fibroblasts, keratinocytes | back 31 C. Helper T cells, macrophages, dendritic cells |
front 32 HIV infection of macrophages and dendritic cells is especially harmful because these cells normally perform which role? A. Kill helminths directly B. Produce thyroid hormone C. Form epithelial barriers D. Activate killer T cells | back 32 D. Activate killer T cells |
front 33 One reason AIDS is deadly is that HIV can persist in which state? A. Latent phase B. Spore phase C. Germinal phase D. Vegetative phase | back 33 A. Latent phase |
front 34 HIV spreads efficiently because it hijacks which system? A. Endocrine system B. Immune system C. Skeletal system D. Digestive system | back 34 B. Immune system |
front 35 Untreated HIV-1 infection commonly leads to death within approximately how long? A. 6 months B. 2 years C. 50 years D. 10 years | back 35 D. 10 years |
front 36 People with AIDS are treated with which medication class? A. Antihistamines B. Antiretrovirals C. Glucocorticoids D. Antifungals | back 36 B. Antiretrovirals |
front 37 Some patients naturally control HIV-1 without typical progression. What are they called? A. Elite controllers B. Latent carriers C. Viral amplifiers D. Seronegative hosts | back 37 A. Elite controllers |
front 38 In elite controllers, pattern-recognition receptor signaling increases secretion of which two antiviral cytokines? | back 38 IFN-alpha and IFN-beta |
front 39 IFN-alpha and IFN-beta help elite controllers mainly by blocking which viral process? A. Viral entry B. Antibody production C. Antigen presentation D. Viral replication | back 39 D. Viral replication |
front 40 Some elite controllers have stronger MHC I molecules. Which immune response improves? A. Faster B-cell switching B. Stronger IgE binding C. Faster killer T activation D. Increased eosinophil survival | back 40 C. Faster killer T activation |
front 41 Better MHC I presentation in HIV elite controllers most directly activates which cell type? | back 41 Killer T cells |
front 42 Which feature best explains why HIV is difficult to eliminate after initial infection? A. Fixed surface antigens B. No cellular reservoir C. Immediate immune clearance D. Latent reactivatable reservoir | back 42 D. Latent reactivatable reservoir |
front 43 A virus infects APCs needed for cytotoxic T-cell activation. Which HIV target cell group explains this? A. Eosinophils and basophils B. Macrophages and dendritic cells C. Plasma cells and B cells D. Keratinocytes and fibroblasts | back 43 B. Macrophages and dendritic cells |
front 44 A patient’s HIV mutates repeatedly as it replicates. Which outcome best follows? A. Antigenic variation B. Thymic regeneration C. IgE blockade D. Fas correction | back 44 A. Antigenic variation |
front 45 Which combined features make AIDS especially deadly? A. Low mutation, rapid clearance B. IgE binding, mast activation C. Latency, mutation, APC infection D. Spore formation, toxin release | back 45 C. Latency, mutation, APC infection |
front 46 Immune weakness can result from mutation of how many genes? | back 46 One gene |
front 47 Compared with genetic immunodeficiencies, which category affects millions of people? _______ immunodeficiencies | back 47 Acquired immunodeficiencies |
front 48 Genetic immunodeficiencies are best described as which pattern? A. Rare disorders B. Universal disorders C. Acquired disorders D. Infectious disorders | back 48 A. Rare disorders |
front 49 Which virus is most intensely studied as the cause of AIDS? | back 49 HIV-1 |
front 50 The abbreviation HIV-1 refers to which virus? A. Human T-cell virus one B. Human immunodeficiency virus one C. Herpes immunodeficiency virus one D. Host integration virus one | back 50 B. Human immunodeficiency virus one |
front 51 During acute HIV infection, the dramatic rise in total circulating virus is called what? Viral _____ | back 51 Viral load |
front 52 After acute HIV peaks, viral load decreases mainly because which cells begin working? A. Virus-specific CTLs B. Memory B cells C. Follicular dendritic cells D. Tissue mast cells | back 52 A. Virus-specific CTLs |
front 53 Many viral infections fully clear after the acute phase. What is this clearance called? _____ | back 53 Sterilization |
front 54 Unlike many viruses, full HIV-1 infection enters which long-term phase after acute infection? A. Chronic phase B. Germinal phase C. Vegetative phase D. Allergic phase | back 54 A. Chronic phase |
front 55 During chronic HIV infection, which immune populations initially remain high? _____ and _____ cells | back 55 CTLs and Th cells |
front 56 During chronic HIV infection, Th-cell numbers slowly decrease because HIV does what? _____ them | back 56 Kills them |
front 57 In chronic HIV, CTLs eventually decline because they lose help from which cells? _____ cells | back 57 Th cells |
front 58 Late in untreated HIV, CTL decline causes which virologic change? Viral ____ rises | back 58 Viral load rises |
front 59 Profound immunosuppression in AIDS most directly predisposes to which fatal complication? A. Seasonal allergy B. Autoimmune arthritis C. Opportunistic infection D. Contact dermatitis | back 59 C. Opportunistic infection |
front 60 HIV can initiate latent infection within approximately what time after exposure? A. 24 hours B. 3-4 weeks C. 6 months D. 5-10 days | back 60 D. 5-10 days |
front 61 Latent HIV reservoirs may form before full activation of which system? A. Innate immune system B. Adaptive immune system C. Complement system D. Coagulation system | back 61 B. Adaptive immune system |
front 62 Why does HIV latency form especially early relative to adaptive immunity? A. Antibodies appear immediately B. CTLs mature prenatally C. Adaptation takes about one week D. Neutrophils suppress latency | back 62 C. Adaptation takes about one week |
front 63 HIV reverse transcriptase is especially dangerous because it is highly what? ____-prone | back 63 Error-prone |
front 64 The error-prone nature of HIV reverse transcriptase produces which viral consequence? High _____ rate | back 64 D. High mutation rate |
front 65 HIV escape mutants can arise after approximately how long? A. 3-4 weeks B. 10 days C. 2 years D. 10 years | back 65 B. 10 days |
front 66 Once HIV escape mutants arise, original CTLs usually fail to do what? A. Produce antibody B. Enter lymph nodes C. Recognize them D. Bind complement | back 66 C. Recognize them |
front 67 Which molecule functions as HIV-1’s docking protein? _____ | back 67 CD4 |
front 68 By infecting macrophages and dendritic cells, HIV damages cells needed for which process? A. IgE crosslinking B. CTL activation C. Keratinocyte growth D. Fas signaling | back 68 B. CTL activation |
front 69 HIV-infected immune cells can carry virus from tissues to which site? A. Bone marrow B. Thymic cortex C. Splenic red pulp D. Lymph nodes | back 69 D. Lymph nodes |
front 70 Within lymph nodes, HIV can undergo which change? Faster ________ | back 70 Faster proliferation |
front 71 In lymph nodes, HIV may be coated by antibodies or which other system? A. Coagulation B. Kallikrein C. Complement D. Fibrinolysis | back 71 C. Complement |
front 72 Opsonized HIV in lymph nodes can become trapped on which stromal immune cell? A. Macrophages B. Follicular dendritic cells C. Mast cells D. Neutrophils | back 72 B. Follicular dendritic cells |
front 73 ART improves survival but does not do what? A. Eliminate HIV B. Block replication C. Target viral enzymes D. Slow progression | back 73 A. Eliminate HIV |
front 74 ART works mainly by targeting components of which process? A. Antibody class switching B. Complement activation C. Viral replication cycle D. T-cell thymic selection | back 74 C. Viral replication cycle |
front 75 The main clinical benefit of ART is best described how? A. Sterilizes latent reservoirs B. Lengthens patient survival C. Restores thymus completely D. Prevents all cancers | back 75 B. Lengthens patient survival |
front 76 Patients on ART have increased risk of cancer and which neurologic complication? _____ disorders | back 76 Cognitive disorders |
front 77 _____-term ART-treated HIV patients have increased risk affecting kidneys, liver, bone, and the heart. | back 77 long |
front 78 Average lifespan on ART is approximately how much shorter than uninfected individuals? A. 5 years B. 10 years C. 15 years D. 20 years | back 78 D. 20 years |
front 79 Approximately what fraction of HIV-infected individuals are elite controllers? A. 3% B. 0.3% C. 10% D. 30% | back 79 B. 0.3% |
front 80 Some elite controllers can control HIV infection for as long as what duration? A. 30 years B. 10 days C. 3-4 weeks D. 5-10 days | back 80 A. 30 years |
front 81 In some elite controllers, CTLs are described as unusually what? A. Suppressed B. Vicious C. Latent D. Opsonized | back 81 B. Vicious |